Grallator

Fossil samples – e.g. ‘primitive’ bony fish (1, 2), a skull of a temnospondyl ‘amphibian’ (probably a metoposauroid) in dorsal view (3), a skull of an archosaur of the crocodile lineage (probably a phytosaur) in palatal view (4), holotype of the “gliding reptile” Icarosaurus siefkeri [1] (5) and Atreipus-Grallator-type dinosaur tracks (bottom right) – from the Newark Supergroup, i.e. a series of mainly Late Triassic to Early Jurassic sedimentary rocks of eastern North America ↑ Edwin H. Colbert: A gliding reptile from the Triassic of New Jersey. American Museum Novitates, 2230. American Museum of Natural History, New York 1966, digitallibrary.amnh.org, cf. fig. 3 therein.

Fossil samples – e.g. ‘primitive’ bony fish (1, 2), a skull of a temnospondyl ‘amphibian’ (probably a metoposauroid) in dorsal view (3), a skull of an archosaur of the crocodile lineage (probably a phytosaur) in palatal view (4), holotype of the “gliding reptile” Icarosaurus siefkeri [1] (5) and Atreipus-Grallator-type dinosaur tracks (bottom right) – from the Newark Supergroup, i.e. a series of mainly Late Triassic to Early Jurassic sedimentary rocks of eastern North America ↑ Edwin H. Colbert: A gliding reptile from the Triassic of New Jersey. American Museum Novitates, 2230. American Museum of Natural History, New York 1966, digitallibrary.amnh.org, cf. fig. 3 therein.

Original figure caption: .mw-parser-output .smallcaps{font-variant:small-caps}The Middletown Slab covered with the Footprints of Carnivorous Dinosaurs. The tracks are in high relief. Additional notes: Most if not all of these tridactylous (i.e. three-toed) footprints/tracks (but not the actual trackmaker!) are referred to as Grallator or as Grallator-type trace fossils. “High relief” means that these are actually casts of footprints forming a positive relief on the lower surface of the sandstone slab (so-called positive hyporelief). The material that originally formed the mud over which the dinosaurs walked was too friable to be recovered from the quarry in one piece. The slab consists of so called ‘brownstone’ which is the trading name of the sandstone quarried at Middletown, Connecticut. This sandstone belongs to the Lower Jurassic Portland Formation of the Hartford Basin (“Connecticut Valley”) and thus to the upper part of the Newark Supergroup. The trackmakers probably were relatively small ‘primitive’ theropod dinosaurs (coelophysoids) such as Podokesaurus the remains of which were recovered from Lower Jurassic deposits of the Hartford Basin.

Original figure caption: Trackway S1 (Eosauropus sp.), here attributed to a sauropod trackmaker based on pedal synapomorphies; trackmaker is moving towards the south-west. Two consequtive pes impressions of a tridactyl Grallator [i.e. a theropod] trackway can be seen left to the S1 trackway. Note: The tracks are preserved on a bedding plane of a thin siltstone bed of the Late Triassic Fleming Fjord Formation of East Greenland. A) shows a photograph of the trackway(s) as preserved on the bedding plane (i.e. as concave epireliefs); B) shows a color shaded relief map based on a high-resolution photogrammetric 3D-model of the bedding plane; C) is an interpretative outline drawing of the S1 trackway; abbreviations: LM = left manus (i.e. forefoot), LP = left pes (i.e. hindfoot), RM = right manus, RP = right pes, numbers increase in walking direction.

Moyeni dinosaur tracks. Photographs of plaster casts (positives) of Grallator track 6 (A) and Anomoepus track 8 (B) made at the Moyeni tracksite by the authors. Tracks are shown at the same scale (10 cm), and hatching pattern indicates broken surfaces. The Grallator hind foot print was made by pedal digits II–IV; the trackmaker's phalangeal formula was 3–4–5. Digits I and V did not contact the substrate. The rugose texture surrounding the print is the algal mat. The Anomoepus manus–pes couple registers all five manual digits (i–v), four pedal digits (I–IV), the metatarsus (mt), and toe drag marks (dm). Additional structures to the left of the pes are incidental marks made by a different trackmaker.

Moyeni dinosaur tracks. Photographs of plaster casts (positives) of Grallator track 6 (A) and Anomoepus track 8 (B) made at the Moyeni tracksite by the authors. Tracks are shown at the same scale (10 cm), and hatching pattern indicates broken surfaces. The Grallator hind foot print was made by pedal digits II–IV; the trackmaker's phalangeal formula was 3–4–5. Digits I and V did not contact the substrate. The rugose texture surrounding the print is the algal mat. The Anomoepus manus–pes couple registers all five manual digits (i–v), four pedal digits (I–IV), the metatarsus (mt), and toe drag marks (dm). Additional structures to the left of the pes are incidental marks made by a different trackmaker.

Lamont-Doherty Earth Observatory specimen of Ichnogenus Grallator

Lamont-Doherty Earth Observatory specimen of Ichnogenus Grallator

Lamont-Doherty Earth Observatory specimen of Ichnogenus Grallator

Lamont-Doherty Earth Observatory specimen of Ichnogenus Grallator

Lamont-Doherty Earth Observatory specimen of Ichnogenus Grallator

Lamont-Doherty Earth Observatory specimen of Ichnogenus Grallator

Lamont-Doherty Earth Observatory specimen of Ichnogenus Grallator

Lamont-Doherty Earth Observatory specimen of Ichnogenus Grallator

Lamont-Doherty Earth Observatory specimen of Ichnogenus Grallator

Lamont-Doherty Earth Observatory specimen of Ichnogenus Grallator